In general, the integrity of fluid-based, interconnected pipeline systems must be tested for leaks. This type of testing is applicable to oil pipeline systems, commercial wastewater systems, and residential plumbing systems, among others. During the construction of a building, for example, a plurality of drainage pipes are interconnected so that sewage or waste water may flow from multiple sources down a single drainage system. The pipeline system is inspected for leaks and must pass government inspection before occupancy is permitted.
Pipes for tubs, showers, sinks, and toilets, are interconnected and make a final connection to a stand-pipe or vent stack that extends several feet above ground level. The standpipe is coupled to the pipeline system to prevent the formation of a vacuum generated by fluid in the pipes. A test tee is typically installed at the junction between the stand-pipe and the remainder of the pipeline system to create a site for testing the integrity of the system. A conventional test tee includes a T or Y fitting in an elongate tubular member, which is permanently installed in the stand-pipe or the stack of sewage sections. The test tee includes an accessible opening, which is conventionally used to isolate a portion of a building's plumbing system with an air-filled balloon or other stopper device or to attach a device for filling the stand-pipe with water. Multiple test tees can be installed throughout large or multi-level pipeline projects to test specific areas.
To test the pipeline system, the stand-pipe is filled with water through the test tee and the pressurized pipeline system is inspected to determine if any leaks exist. Once the inspection of the system is completed, the water is released from the stand-pipe through the test tee and usually gushes onto the ground or floor.
Various prior art devices have been designed which are removably attachable to the test tee to cap its opening so that the pipeline system stays pressurized until inspected. One such device is a bushing and hose bib arrangement (“bushing/bib”) made of off-the-shelf, standardized parts in which a plastic bushing is connected to a brass hose bib (spigot). The bushing/bib is screwed into the opening of the test tee. A plumber fills the pipeline system with water from a garden hose and seals the stand-pipe temporarily by closing the spigot. After the test is complete, the bushing/bib must be removed and replaced with a permanent cap.
One problem with the bushing/bib and other prior art devices is the cost of using these devices. Having a brass component, the bushing/bib is relatively expensive, even though it is reusable. However, the bushing/bib devices are often stolen—after the inspection—before the plumber can return to replace the bushing/bib with an inexpensive, permanent threaded plastic cap to cover the test aperture.
Another problem with the prior art devices is the potential water damage that can occur when the devices are removed after testing. The prior art devices are not designed to be permanent fixtures. Such a device cannot become a permanent fixture of the system and must be removed. When the prior art device is removed—either by a plumber or by a thief—a considerable volume of water flows outward from the opening of the test tee, which sometimes causes flooding and damage to the floor of the building and surrounding areas.
On the other hand, since such prior art testing devices are not intended to be permanent fixtures, significant problems can also arise if they are inadvertently left in the test fixture, and construction is completed. For example, U.S. Pat. No. 5,076,095 to Erhardt discloses a device having a paddle-shaped sealing member coaxially coupled to a freely rotatable threaded cap member which removably engages the tee fitting in a plumbing system vent stack. The paddle selectively extends across and seals the pipeline. The Erhardt device includes a one-way check valve to introduce pressurized fluid into the plumbing system above the aforementioned paddle inside the tee fitting. The paddle-shaped sealing member of the Erhardt device extends across, and either entirely blocks or partially restricts, the flow path in the tee. Many city codes prohibit any such blockage or restriction in the plumbing line; thus, if one forgets to remove the Erhardt device before covering over the plumbing line with drywall, the resulting structure is in violation of the city code. Additionally, if the Erhardt device were inadvertently left within the test tee, the paddle-shaped sealing member could later rotate to its closed position (i.e., upon a sudden rush of water) and seal off the pipe, leading to either undesired vacuums within the plumbing system, or possibly flooding. Furthermore, were the aforementioned Erhardt device inadvertently left in the test tee, and then covered over by drywall, water could eventually leak out from the test tee behind walls of the structure, causing the formation of mold.
Therefore, it is an object of this invention to provide a leak-testing device that significantly contributes to the ease and low cost involved in the inspection of a pipeline system for leaks. It is a further object of the invention that the leak-testing device may serve as a permanent attachment to the test tee so that removal is not required, thereby avoiding the expenses of having a plumber return to replace it or of having it stolen. It is a further object of this invention to have a leak-testing device made of inexpensive materials.
It is a further object of the invention that the leak-testing device may serve as a permanent attachment to the test tee so that removal is not required, thereby avoiding flooding of the foundation of the building or the area beneath the fluid-based pipeline system.
Another object of the present invention is to provide a leak-testing device that may be attached to the test tee of a pipeline system in such a way that fluid may be channeled through the testing device into the test tee.
It is a further object of the invention that the leak-testing device is leakproof so that no fluid escapes out of the testing device.
Further objects and advantages of the present invention will become apparent from the study of the following portions of this specification, the claims and the attached drawings.